Isoinertial lifting device

Abstract

An isoinertial lift machine is described which can be used to evaluate and train patients in the static and dynamic lift modes. The machine consists of an arm which can be positioned on a vertical column. At the end of the arm, various size attachments and handles can be attached. The arm also carries a force sensor that measures the forces applied to the handles. In the static mode, the arm is positioned at a desired height and locked in place. The patient lifts on the handle, and the force sensor registers the lifting force. Since the handle does not move during the lift, the mode is called static. In the dynamic mode, the arm/handle moves in the vertical direction during the lift. A resistance mechanism is used to resist the lifting force applied by the user at the handle. The resisting force is always pulling the arm down, both in the lifting and the lowering motion. The resisting force remains constant throughout the range of motion during lifting. The isoinertial machine can also be used in the static mode. The machine also allows the user to test pushing and pulling loads in static mode only.

What is claimed is: 
     
       1. A device for exercise and evaluating of both applied dynamic and static force which comprises an upright standard having a horizontal arm mounted thereon for vertical movement on said standard in a dynamic mode, said arm having a force sensor means for registering applied force attached on the distal end thereof and handle means attached to said force sensor means for applying force to said arm in either the horizontal or vertical direction; said arm being connected to first elongated, flexible connector means which is attached to a rotatable drive pulley mounted on a shaft such that said vertical movement of said arm causes rotation of said shaft; second flexible elongated connector means connecting a weight means to a rotatable weight pulley also mounted on said shaft such that rotation of said weight pulley causes vertical displacement of said weight means; clutch means mounted on said shaft for causing engagement/disengagement of said drive pulley and weight pulley to cause the respective pulleys to turn together or independently of one another; said horizontal arm being provided with means for locking it in position on said standard in the static mode to prevent said vertical movement in response to force applied thereto; and said force sensor means being connected to means for evaluating and recording applied force in both the static and dynamic modes. 
     
     
       2. The device of claim 1 in which a counterweight means is attached on said first connector means to oppose vertical movement of said arm. 
     
     
       3. The device of claim 1 wherein a brake means is provided on said shaft for opposing rotation thereof. 
     
     
       4. The device of claim 1 wherein each of said first and second flexible connectors are a continuous loop, the ends of which connect respectively to said arm and said weight means. 
     
     
       5. The device of claim 1 wherein said connector means are cables.